Officers responded to reports of shots fired at a home on the 1200 block of North Mountain View Avenue Saturday morning.
That's where they found the two victims, apparently shot to death. One was found inside the home while the other one was outside nearby.
They have been identified as 29-year-old Rudolfo Trujillo of Rialto and 33-year-old Daniel Aguilar of Fontana. Investigators say they're at a loss about what may have led to the double murder.
"Through the investigation, we learned that they are cousins. At this point in the investigation, we are not able to rule out if it's gang related, drug related or domestic related," said Sgt. Gary Robertson with the San Bernardino Police Department.
If you have any information about this incident, you're urged to call San Bernardino police at (909) 384-5656.